Continuous Microfiber Wire Mandrel-Less Biofabrication for Soft Tissue Engineering Applications.

Suture materials are the most common bioimplants in surgical and clinicalpractice, playing a crucial role in wound healing and tendon and ligamentrepair. Despite the assortment available on the market, sutures are stillaffected by significant disadvantages, including failure in mimicking themechanical properties of the tissue, excessive fibrosis, and inflammation.This study introduces a mandrel-less electrodeposition apparatus to fabricatecontinuous microfiber wires of indefinite length. The mandrel-lessbiofabrication produces wires, potentially used as medical fibers, withdifferent microfiber bundles, that imitate the hierarchical organization ofnative tissues, and tailored mechanical properties. Microfiber wiremorphology and mechanical properties are characterized by scanning electronmicroscopy, digital image processing, and uniaxial tensile test. Wires aretested in vitro on monocyte/macrophage stimulation and in vivo on a ratsurgical wound model. The wires produced by mandrel-less deposition showan increased M2 macrophage phenotype in vitro. The in vivo assessmentdemonstrates that microfiber wires, compared to the medical fibers currentlyused, reduce pro-inflammatory macrophage response and preserve theirmechanical properties after 30 days of use. These results make this microfiberwire an ideal candidate as a suture material for soft tissue surgery, suggestinga crucial role of microarchitecture in more favorable host response.